Color photography



March 8, 1932.` 1'. B- HARRIS, 1,848,714

I COLOR PHOTOGRAPHY Filed March 5, i929 Patented Mar. 8, 1932 UNITED STATES PATENT OFFICE JOSEPH E. mars, JE., or Los ANGELES, 'CALIFORNIA COLOR PHOTOGRAPHY Application 1ed March 5, 1929. Serial No. 344,185.

color-photograph, that is, a photograph which exhibits an image of a subject colored corresponding to the coloring of the subject.

Heretofore, it has been proposed to form Vtwo registered super-imposed images in the same picture space, one of onecolor and the other of a substantially complementary color. These colors have been secured usually, one

by a toning processl and the other by a dyeing process or both by a dyeing process.

A principal object of applicants invention is to provide a process by which at least two substantially complementary'colored superimposed images', in the same image space, in a single coating, on one side only of a carrier, may be obtained by methods which involve the toning with metallic salts of one image and its subsequent dyeing and the 'toning of the other image.

Gther objects and advantages will appear as the description of a particular manipulation involving the novel features of applicants invention progresses and the novel features will be' particularly pointed out in the appended claims.

In describing the invention in detail and the particular physical product resulting from the application of the process selected to illustrate the invention reference is had to the,l accompanying drawings wherein has been illustrated a particular pliysical product resulting from the practice and application of the invention and wherein like characters of reference designate corresponding parts throughout the several views, and in which;

Figure l, is a schematic representation of a subject; Fig. 2, is a schematic representation of a red color selection negative reprewhat is known as al sentative of the reds in the subject, Fig. l; Fig. 3, is a green color selection negative representative of the vgreen in the su ject, Fig. 1;'Fig. 4, is a schematic representation of a positive obtained by the use of the Vnegative illustrated by Fig. 2; Fig. 5, is a schematic representation of the positive illustrated by Fig. 4 after having been toned; Fig. 6 is a schematic representation of the positive illustrated by Fig. 5 after printing therein by the negative, Fig. 3, and development; Fig.

7 is a schematic representation of the posil tive Fig. 6 after being dyed in the toned portions; Fig. 8, is a schematic representation of the positive Fig. 7 after being toned; Fig. 9, is a schematic view illustrating printing from a negative; Fig. l0, is a schematic view illustrating another method of printing from a negative.

Applicant tangle as a subject by which application of this process. This multi-.colored rectangle is illustrated by Fig. l. It is divided by two diagonal lines forming foui triangles. One triangle, 1, is colored red; another 2, is white; another, 3, is colored green, and the fourth, 4, is black.

The first step in carrying out applicants process is to secure two color'selection negatives of the subject, Fig. 1. This is done inthe usual and well known manner. The finished red color selection negative is illustrated by Fig. 2. As the red color selection negative, Fig. 2, is a negat-ive made from the subject l and in accordance with the usual methods the triangle 1`will be black; the triangle 2 will be black; the triangle 3 will be white; and the triangle 4 will be white.

As the green color selection negative, Fig. 3, is a negative of the subject, Fig. 1, and is has selected a multi-colored recto illustrate the made in accordance with the usual methods,

The first step after obtaining the negatives is to obtain a print of one of them in a photographic emulsion preferably, light sensitive silver salt borne on a transparent carrier. A suitable transparent carrier bearing a suitable photographic emulsion would be the'ordinary and well known motion picture film stock. The stock used is illustrated in Fig. 9 in which 5 is the carrier and 6 is the photographic emulsion. Fig. 9 also illustrates the manner in which the print is to be made as 7 designates the carrier of the negative Fig. 2 and 8 designates the image carrying layer thereon. The negative is applied to the back of the carrier and the light 9 is positioned back of the negative. By such an arrangement and by proper regulation of the light value emitted by the light source 9 the image formed in the photograph emulsion will lie substantially adjacent the carrier 5, that/is, within the interior of the emulsion 6. A print so made when developed would appear as shown schematically in Fig. 4 in which..the triangle 1 would be white; the triangle 2 would be white; the triangle 3 black.; and the triangle 4 black. The development would be carried out in the usual manner except that at no time must the print be exposed to light. The developer preferably would be one usable in neutral of acid solution such as diamidophenol. v

The development should be followed by a short wash and then the print should be immersed for about ten minutes in a bath which consists of:

50 grams sodium citrate 10 grams copper sulphate 5 grams potassium ferricyanide 1000 ccs. water The bath will tone and mordant the print in those portions containing developed silver a sort of red-brown.

The print should next be given a 5 minute wash in water.

Following the Wash the print should be immersed in a clearing bath for about ten minutes. A suitable clearing bath would be as follows:

12 grams ammonium bromide 12 grams potassium bichromate 2 liters water.

The next step is to form an image in they photographic emulsion of the same print aS shown by Fig. 5 by the use of the greencolor selection negative, Fi 3. This 1s done by positioning` the negatlve and print as illustrated by ig. 10, in which 5 designates the carrier and 6 the photographic emulsion of the print Fig. 5 and 11 designates the carrier and 12 the image carrying layer of the negative, ,Fig 3. The position of the printing light is illustrated by 13. By so positionmg the negative Fig. 3 in relation to the print Fig. 5 as shown in Fig. 10 full advantage will be taken of the undeveloped 1i ht sensitive silver salt in the outer portion, t at is, the portion remote from the carrier 5 of the photographic emulsion 6. Itis of course understood that the negative, Fig. 3, must be so positioned in relation to the print, Fig. 5, that the latent image will be formed in proper registration with the toned and mordanted image already present.

The next operation is to develop. A suitable developer is as follows:

5 grams diamidophenol 50 grams sodium sulphite 1 gram potassium bromide 5 ccs. lactic acid 1000 ccs. water phate of a concentration of about 10 grams to 1000 ccs. of water. By this operation the first image, which was somewhat weakened by the action of the second development will be restored.

The result of a second development and the treatment withthe copper sulphate bath is to cause the print to appear as shown schematically in Fig. 6 in which triangle 1 is black; triangle 2 is white; triangle 3 is red; and triangle 4 is colored with a mixture of both red and black. i

After a wash in water for about 10 minutes the print is ready to receive the dye. A suitable dyeing solution is one containing basic dyes and may be made as follows:

1 gram auramine, dissolved in alcohol 2 grams victoria green 2 ccs. acetic acid i 1000 ccs. water The dyeing solution would be allowed to act until the proper color density is obtained which would be about 12 minutes in the usual case. t

The next operation is to fix the print. This would be done in a non-acid sodium thiosulfate bath. This bath not only removes all of the undeveloped light sensitive silver salt but also fixes the dye soi' that the dye is not eiected by the long washing in water which then follows.

The appearance ofthe print after the wash Will then be as illustrated by Fig. 7 in which triangle 1 will be black; triangle 2 Will be white; triangle 3 will be green; and the triangle 4 will be colored by a mixture 'of green and black.

After the long washing the print is immersed in the cop-per salt toning bath hereinbefore given. A proper density Will be obtained by about ten minutes immersion. After fixing in thiosulphate and a thorough Washin Water the ilmis dried and Will appear as shown schematically in Fig. 8 in Which the triangle 1 Will be red; the triangle 2 will be White; the triangle 3 will be green; and the triangle 4 containing a mixture of both green and red will, by transmitted light, appear black. 7 The colors of the triangles as last described are identical with the similarly positioned triangles in the subject Fig. 1.

The operation of the process has resulted in the production of a transparent carrier having a coating on one side only in which in the same picture area two registered image without affecting the color of the first image. p

4. A photo aphic process which consists in forming a atent image in a photographic emulsion, developing, toning with a metallic vsalt and after clearmg with a bath of ammonium bromide and potassiumbichromate in water solution, forminganother latent image, developing and then dyeing the toned image in a water solution of a basic dye, then after fixing, toning the second formed image with a metallic salt.

JOSEPH B. HARRIS, JR.

superimposed complementary color images have been formed, one a dyed green and the other toned red.

Although applicant has illustrated the principle of his invention by describing the steps of a novel process which result in a novel-product, nevertheless, it is to be understood that the particular manipulation described and the product formed does not exhaust the possible manipulation and products lying Within the domain of the invention.

What I claim as new and desire to .secure i by Letters Patent of the United States, is:

1. A photographic process which consists in forming al latent image in a photographic emulsion, developing, toning with `a copper salt and after clearing with a bath of ammonium bromide and potassium ubichromate in Water solution forming another latent image in the :samerphotographic emulsion, developing and then dyeing the toned image in a Water solution of a basic dye, then after fixing, toning the second formed image with a copper salt.

2. A photographic process which consists i in forming a metallic image in a photographic emulsion, toning said image and clearing With a bath of ammonium bromide and potassium bichromate in Water solution and thereafter forming a latent image in the said photographic emulsion,developing and fixing said last mentioned image, and after dye ing the first mentioned image With a basic ,dye toning the last mentioned image.

3. The process which consists in first forming a silver image in a photographic emulsion, then toning with acopper salt that imin the same photographic emulsion, y

age substantially a redbrovvn, then forming another silver image in the same photographic emulsion, then green dyeing the first i mentioned image With a basic dye, fixing, f

and then vred toning the second mentioned 

